Lightness perception can be affected by surface curvature from stereopsis

It is demonstrated that lightness perception can be affected by shape from stereopsis. The starting point was a report by Knill and Kersten that the perceived lightness of a monocularly viewed surface can be affected by outline-contour cues indicating that the surface is three-dimensional (3-D). In that study stimuli consisted of two equally sized abutting regions each having the same vertical linear-intensity ramp, so that the horizontal abutting boundary of the two patches created a sharp change in intensity. When this version of the Craik-O'Brien-Cornsweet stimulus has a rectangular outline, it exhibits the standard simultaneous contrast illusion: equivalent patches in the top and bottom regions appear to have different brightness despite having the same luminance. Knill and Kersten replicated this phenomenon with stimuli whose outline-contour cues were consistent with a flat (planar) surface. They found, however, that the illusion was greatly reduced in stimuli with outlines consistent with two abutting 3-D quarter cylinders, for which equivalent regions in the two halves appeared of similar lightness. Knill and Kersten interpreted this effect in terms of surface-lightness computations that took into account 3-D surface shape to achieve an integrated interpretation of the luminance and shape data. In the present report three experiments are described for which these earlier findings were taken as the starting point. In the first experiment the results were replicated by the use of a different methodology. In the second experiment it was shown that shape-from-stereo can produce similar effects on lightness perception to that caused by shape-from-contour. Real 3-D objects with curved surfaces, luminance profiles of the Knill and Kersten type, and carefully controlled outline-contour cues were used so that the objects appeared flat when viewed monocularly but curved in 3-D when seen binocularly. The third experiment was a control confirming that the stereo effect was not simply due to differences caused by monocular versus binocular viewing. It is concluded that the human visual system uses stereo cues, as well as outline-contour cues, in the interpretation of luminance data to recover surface lightness.

Major degradation products of basic fibroblast growth factor: detection of succinimide and iso-aspartate in place of aspartate

The degradation products of basic fibroblast growth factor (bFGF) were isolated by ion exchange HPLC (HP-IEC) and characterized. The predominant product at pH 5 was a succinimide in place of aspartate15 as determined by LC/MS, N-terminal sequencing, and susceptibility to degradation at pH > 6.5. The rate of appearance of the succinimidyl-bFGF at 22 degrees C was comparable to that reported for small peptides, consistent with a high flexibility predicted for asp15-gly. Tryptic mapping together with [3H]-methylation indicated that iso-aspartate was formed at the position of asp15. Size exclusion HPLC indicated the presence of intact and truncated dimers and trimers which associated through disulfide linkages. Two truncated monomer forms were found that co-eluted by HP-IEC; the cleavages were determined to be at asp28-pro and asp15-gly using LC/MS and N-terminal sequencing. These degradation products which occurred at sites that are away from receptor or heparin binding domains of bFGF remained bioactive in a cell proliferation assay.

Second trimester ambulatory blood pressure in nulliparous pregnancy: a useful screening test for pre-eclampsia?

OBJECTIVE

To assess the effectiveness of second trimester 24-hour ambulatory blood pressure measurement as a screening test for pre-eclampsia.

DESIGN

Prospective interventional study.

SETTING

John Radcliffe Maternity Hospital, Oxford, and Queen Charlotte's and Chelsea Hospital, London.

SUBJECTS

One hundred and sixty-two normotensive nulliparous women recruited at hospital booking clinics.

INTERVENTION

Ambulatory blood pressure was measured at 18 and 28 weeks gestation using the TM2420 monitor.

MAIN OUTCOME MEASURE

The development of pre-eclampsia.

RESULTS

Awake systolic and mean arterial pressures were significantly increased (P < 0.02) at 18 weeks in those who later developed pre-eclampsia. Those differences were more apparent at 28 weeks at which time the diastolic pressure was also increased (P < 0.01). At both stages of gestation the higher readings were sustained during sleep so that the awake-sleep differences were similar in relation to each outcome. The group with incipient pre-eclampsia had a significantly faster heart rate at both 18 and 28 weeks (P < 0.002) The sensitivity in predicting pre-eclampsia for a mean arterial pressure of 85 mmHg or greater at 28 weeks was 65%, with a positive predictive value of 31%. The sensitivity and positive predictive value for a test combining a mean arterial pressure of 85 mmHg or greater and a heart rate of 90 bpm or greater were 53% and 45%, respectively.

CONCLUSION

Although second trimester ambulatory blood pressure is significantly increased in women who later develop pre-eclampsia, the predictive values for blood pressure alone are low. The efficiency of the test is increased by combining the awake ambulatory heart rate and blood pressure measurement together. If an effective method for preventing pre-eclampsia becomes available (commencing at 28 weeks gestation), then awake ambulatory blood pressure and heart rate may have some clinical value as a screening test.

Interaction of stereo, texture and outline cues in the shape perception of three-dimensional ridges

We report five psychophysical experiments that employed a cue conflict paradigm to investigate integration by the human visual system of surface shape information from stereo, texture and outline cues. The experiments used convex parabolic and triangular three-dimensional ridge stimuli, with amplitudes (base to peak) in the range 3-9 cm, viewed from 57 cm. The observers' task was to judge ridge amplitude using a scale of two-dimensional drawings of ridge profiles. Cue integration was studied using both vertically and horizontally oriented ridges and both real ridges and stereograms of ridges. The main findings were: (a) stereo strongly dominated all horizontal ridge stereograms; (b) texture and outline cues strongly dominated low (3-6 cm) but not high (9 cm) amplitude vertical ridge stereograms; (c) stereo strongly dominated all real ridge stimuli. These results are evidence against explanations of the vertical/horizontal stereo anisotropy which propose that it derives from stereo mechanisms being tuned only to disparity cues with non-zero second-order spatial derivatives or to disparity discontinuities. They also show that radically different results can be obtained when stereo mechanisms are explored using stereograms and real surfaces and possible reasons for this are discussed.

Noninvasive assessment of the maternal cerebral circulation by transcranial Doppler ultrasound during angiotensin II infusion

OBJECTIVE

To examine the relationship between experimentally induced increments in blood pressure and maternal middle cerebral artery flow velocity patterns measured by transcranial Doppler ultrasound (TCD).

DESIGN

Prospective experimental study.

SETTING

John Radcliffe Maternity Hospital, Oxford.

INTERVENTION

Middle cerebral artery flow velocity waveforms were measured using 2 MHz pulsed Doppler ultrasound via the temporal cranial approach at 28 weeks gestation before, during and 10 min following an angiotensin II infusion.

SUBJECTS

101 normotensive primiparous women at 28 weeks gestation.

RESULTS

A significant rise in blood pressure and fall in heart rate were demonstrated between pre-infusion and maximum angiotensin II infusion (maximum blood pressure) recordings. Simultaneous changes were observed in all flow velocity indices, shown as a decrease in systolic velocity and pulsatility index, and an increase in diastolic and mean velocity (P < 0.0001). These values all returned to baseline levels 10 min post infusion (P < 0.0001). Statistical analysis suggested that the change in flow velocity is related to the rise in blood pressure rather than the direct effect of angiotensin II on the cerebral circulation.

CONCLUSION

Transcranial Doppler can detect changes in the cerebral circulation associated with alterations in blood pressure during pregnancy. The technique needs to be evaluated further in hypertensive disease.

Umbilical artery resistance index as a screening test for fetal well-being. II: Randomized feasibility study

To determine whether the time taken for fetal assessment could safely be reduced by preliminary screening with Doppler ultrasound, 897 women having fetal assessment in the high-risk unit of the John Radcliffe Hospital, Oxford, were randomly allocated to two groups. In the Doppler group, preliminary assessment was by umbilical artery resistance estimation, and in the fetal heart rate (FHR) group by computerized FHR analysis. To minimize the risk of failing to recognize fetal distress, the criteria for using the nonallocated method as well were deliberately conservative. Thus, 66% of the 1869 Doppler studies done in the Doppler group and 39% of the 2069 FHR tests done in the FHR group needed to be followed by the nonallocated tests. Trained nursing staff performed the Doppler studies as part of their routine duties. Doppler studies were unsuccessful in obtaining a result on 26% of the occasions. Under the above clinical circumstances, preliminary Doppler screening did not reduce the time taken for fetal assessment. There were no significant differences in perinatal outcome between the groups, except that emergency as opposed to elective cesareans were less frequent in the Doppler group. As this finding was not predicted by previous hypothesis, it needs to be confirmed.

Combined blunt traumatic rupture of the heart and aorta: two case reports and review of the literature

Blunt chest trauma resulting in combined aortic disruption and cardiac rupture, although a common autopsy finding, was found reported only once previously in a surviving patient. We report two cases repaired through a left posterolateral thoracotomy in which the cardiac injury was unsuspected and presented as an intraoperative finding of hemopericardium. With improved emergency resuscitation in the field and faster transport of these cases to tertiary care centers, this combination of lesions may be seen more frequently. Suggestions for their diagnosis and management are presented.

Effects of insulin on diacylglycerol-protein kinase C signaling in rat diaphragm and soleus muscles and relationship to glucose transport

Insulin was found to provoke rapid increases in diacylglycerol (DAG) content and [3H]glycerol incorporation into DAG and other lipids during incubations of rat hemidiaphragms and soleus muscles. Insulin also rapidly increased phosphatidic acid and total glycerolipid labeling by [3H]glycerol, suggesting that insulin increases DAG production at least partly through stimulation of the de novo pathway. Increased DAG production may activate protein kinase C (PKC) as reported previously in the rat diaphragm. We also observed apparent insulin-induced translocation of PKC from cytosol to membrane in the rat soleus muscle. The importance of insulin-induced increases in DAG-PKC signaling in the stimulation of glucose transport in rat diaphragm and soleus muscles was suggested by 1) PKC activators phorbol esters and phospholipase C stimulation of [3H]-2-deoxyglucose (DOG) uptake and 2) PKC inhibitors staurosporine and polymixin B inhibition of insulin effects on [3H]-2-DOG uptake. Although phorbol ester was much less effective than insulin in the diaphragm, phospholipase C provoked increases in [3H]-2-DOG uptake that equaled or exceeded those of insulin. In the soleus muscle, phorbol ester, like phospholipase C, was only slightly but not significantly less effective than insulin. Similar variability in effectiveness of phorbol ester has also been noted previously in rat adipocytes (weak) and BC3H1 myocytes (strong), whereas DAG, added exogenously or generated by phospholipase C treatment, stimulates glucose transport to a degree that is quantitatively more comparable to that of insulin in each of the four tissues. Differences in effectiveness of phorbol ester and DAG could not be readily explained by postulating that the latter acts independently of PKC, because DAG provoked the apparent translocation of the enzyme from cytosol to membranes in rat adipocytes, and effects of DAG on [3H]-2-DOG uptake were blocked by inhibitors of PKC in both rat adipocytes and BC3H1 myocytes. Collectively, our findings provide further support for the hypothesis that insulin increases DAG production and PKC activity, and these processes are important in the stimulation of glucose transport in rat skeletal muscle and other tissues.

Isotretinoin therapy for acne vulgaris: results in an Irish population

The results of treatment of cystic and antibiotic-resistant acne vulgaris in 96 consecutive patients with the oral retinoid isotretinoin (13-cis-retinoic acid; Roacentane) are reported retrospectively. The results show that the drug, while toxic in the short term, is highly effective in clearing acne.

Assessment of inhaler technique in general practice

71 Patients who were using inhalers in an inner city Dublin teaching practice were assessed by the author over a four month period to see if they were using their inhalers properly. 18 (25%) had perfect technique, 26 (37%) had adequate technique and 27 (38%) had poor technique. The patients most likely to have poor technique were those using a Metered Dose Inhaler (M.D.I.), patients using inhalers for less than one year and patients with a diagnosis of C.O.A.D. as opposed to Asthma. Of the 53 patients who had less than perfect technique 37 showed an initial improvement with training. This Author suggests that all patients should be fully evaluated before starting on inhalers and the most appropriate delivery system selected for them. They should be carefully instructed on its correct use and arrangements made for regular follow up to ensure good inhaler technique. This should lead to a greater clinical response and improved patient compliance.

Management of spontaneous intracranial haemorrhage

One hundred and six patients with suspected or confirmed spontaneous intracranial haemorrhage were analysed to determine the management and referral patterns. The cases were classified into six groups on the basis of the computerised tomography (CT) scan/lumbar puncture (LP) findings. Subarachnoid haemorrhage was the commonest lesion. Thirty-four point four per cent of these were complicated. LP was performed inappropriately in a large number of cases. Late referral was a problem in some instances. In suspected intracranial haemorrhage CT scan is the investigation of choice. Lumbar puncture should be deferred and only performed following consultation with a neurosurgeon.

Integration of stereo and texture cues in the formation of discontinuities during three-dimensional surface interpolation

A series of stereograms are presented which demonstrate that texture boundaries can strongly influence the perception of discontinuities between neighbouring three-dimensional (3-D) surfaces portrayed by means of stereo cues. In these demonstration figures, no stereo information is available in the immediate vicinity of the boundary between the two 3-D stereo surfaces because all texture in that region is removed in one eye's view. On the other hand, various forms of texture boundary information are provided in the resulting monocular region. This stimulus paradigm is used to explore the question: what influence does texture boundary information have on the nature of the perceived 3-D surface that is interpolated between two stimulus regions which carry stereo cues? It is shown that if a clear-cut texture boundary is present in the monocular region then this is used by the human visual system to fix the perceived location of 3-D crease and step surface discontinuities between the stereo regions. Collett (1985) explored this issue with a similar methodology and reported weak and unreliable assistance from monocular texture boundaries in helping shape 3-D stereo surface discontinuities. The strong and robust phenomena demonstrated here seem to rely on two main differences between the present stimuli and those of Collett. In the present stimuli, figurally continuous textures containing strong texture boundaries are used, together with a technique for minimising the complications, including binocular rivalry, that arise from the borders of the stimulus regions present in only one half of each stereogram.

Serum vitamin D metabolites in very low birth weight infants with and without rickets and fractures

Seventy-one very low birth weight (less than or equal to 1500 gm) infants were studied to determine the sequential changes in serum vitamin D metabolite concentrations between infants with and without radiographically documented rickets, fractures, or both (R/F). Usual intake of vitamin D included 20 IU/kg/day from parenteral nutrition or 400 IU/day supplementation with enteral feeding. Radiographs of both forearms and serum samples were obtained at 3, 6, 9, and 12 months. Twenty-two infants had R/F. At 3 months, significantly lower mean (+/- SEM) serum phosphorus levels (4.5 +/- 0.4 vs 6.1 +/- 0.2 mg/dl), higher 1,25-dihydroxyvitamin D (1,25-[OH]2D) concentrations (96 +/- 5 vs 77 +/- 4 pg/ml), and higher free 1,25-(OH)2D index (1,25-[OH]2D:vitamin D binding protein ratio; 5.2 +/- 0.3 x 10(5) vs 4.0 +/- 0.2 x 10(5] were found in the R/F group. These values returned to normal and were similar between groups on subsequent measurements. Serum calcium, magnesium, and 25-hydroxyvitamin D (25-OHD) concentrations were normal and similar between groups. In both groups, serum vitamin D binding concentrations increased initially but remained stable and normal beyond 6 months. We conclude that in very low birth weight infants with R/F, the vitamin D status (as indicated by serum 25-OHD concentrations) is normal, and that lowered serum phosphorus levels, higher serum 1,25-(OH)2D levels, and a higher free 1,25-(OH)2D index support the thesis that mineral deficiency (especially of phosphorus) may be important in the pathogenesis of R/F in small preterm infants.

Cardiac and peripheral circulatory responses to angiotension and vasopressin in dogs

To determine the cardiac and peripheral circulatory responses to changes in afterload with angiotension and vasopressin, we increased mean aortic pressure 25% and 50% above control in splenectomized and ganglion-blocked dogs. We compared these responses to similar mechanical increases in aortic pressure produced by partial balloon occlusion of the descending aorta. With 25% or 50% increases in aortic pressure, angiotensin, vasopressin, and balloon inflation produced no changes in heart rate, right atrial, and mean pulmonary artery pressures. At 25% increase in aortic pressure, cardiac output was maintained with angiotensin and balloon occlusion but decreased with vasopressin. At 50% increase in aortic pressure, cardiac output was maintained with only balloon occlusion and decreased with both angiotensin and vasopressin. Whenever cardiac output fell, central blood volume did not increase as after-load increased. These changes in preload can be explained by alterations in the venous circulation. Vasopressin did not alter venous compliance or unstressed vascular volume but increased resistance to venous return. Angiotensin also increased resistance to venous return but decreased venous compliance and did not change unstressed vascular volume. Balloon occlusion had no effects on these parameters. We conclude that: (a) angiotensin caused significant venoconstriction resulting in maintenance of cardiac output at 25% but not 50% increase in aortic pressure; (b) vasopressin increased the resistance to venous return without venoconstriction; this resulted in a fall in cardiac output even with a 25% increase in aortic pressure; and (c) the effects of the agents on the venous circulation were independent of the mechanical effects of a pressure increase in the arterial circulation.

Occult gastrointestinal carcinoma causing metastatic clostridial soft-tissue infection. Report of two cases

The association between nontraumatic, metastatic, clostridial soft-tissue infection and malignancy is well recognized, particularly when Clostridium septicum is involved. This report presents two patients with nontraumatic, metastatic, soft-tissue infection due to C. septicum and reviews the English medical literature. Eighty-four percent of the reported patients were found to have colon carcinoma, which was postulated to be the portal of entry. Prognosis is poor, but early recognition and antimicrobial therapy with prompt and aggressive surgical intervention, both for the soft-tissue infection and the abdominal process, may lower the high mortality.

The major lung surfactant protein, SP 28-36, is a calcium-dependent, carbohydrate-binding protein

SP 28-36, a major protein of pulmonary surfactant, has striking amino acid sequence homology with soluble mannose-binding proteins isolated from rat liver and contains residues common to the carbohydrate-binding domains of other mammalian lectins. We have used carbohydrate-affinity chromatography to investigate carbohydrate-binding properties of SP 28-36 isolated from canine and human (alveolar proteinosis patients) lung lavage. SP 28-36 binds to immobilized D-mannose, L-fucose, D-galactose, and D-glucose. The protein binds only weakly to N-acetyl-D-galactosamine and N acetyl-D-glucosamine. Binding is Ca2+-dependent. The threshold Ca2+ concentration is 0.6 mM and maximal binding occurs with 1 mM Ca2+. Bound protein is quantitatively recovered by elution with 2 mM EDTA. Ba2+, Sr2+, and Mn2+, but not Mg2+, can substitute for Ca2+. Unlike some other mammalian lectins, SP 28-36 binds to carbohydrate at pH 5.0. Recombinant human SP 28-36 isolated from the media of Chinese hamster ovary cells, transfected with a DNA construct encoding SP 28-36, has similar carbohydrate-binding activity to the native proteins. Mannose affinity chromatography of the culture medium of Chinese hamster ovary cells results in an efficient purification of the secreted recombinant human SP 28-36.

Peripheral circulatory control of preload-afterload mismatch with angiotensin in dogs

To determine whether changes in the venous circulation were responsible for preload-afterload mismatch with angiotensin, we examined the changes in the heart and the peripheral circulation in six splenectomized dogs after ganglion blockade during an angiotensin infusion to increase mean aortic pressure 25 and then 50%. The peripheral circulation was evaluated by measuring mean circulatory filling pressure (MCFP), arterial compliance, and venous compliance. A 25% increase in mean aortic pressure increased MCFP from 6.2 +/- 0.3 to 7.6 +/- 0.3 mmHg (P less than 0.001) but did not change cardiac output, heart rate, or stroke volume. Systemic vascular resistance increased (P less than 0.01) from 0.50 +/- 0.02 to 0.59 +/- 0.03 mmHg X min X kg X ml-1. Arterial and venous compliances decreased (P less than 0.01) from 0.08 +/- 0.03 to 0.06 +/- 0.03 ml X mmHg-1 X kg-1 and from 2.1 +/- 0.1 to 1.6 +/- 0.1 ml X mmHg-1 X kg-1, respectively. A 50% elevation in mean aortic pressure increased MCFP from 7.1 +/- 0.4 to 9.5 +/- 0.9 mmHg (P less than 0.001) but did not change heart rate. At this level of aortic pressure, cardiac output and stroke volume decreased (P less than 0.01) 12 and 19%, respectively, whereas systemic vascular resistance increased (P less than 0.001) from 0.48 +/- 0.03 to 0.83 +/- 0.05 mmHg X min X kg X ml-1. Arterial and venous compliances decreased (P less than 0.01) from 0.08 +/- 0.01 to 0.05 +/- 0.01 ml X mmHg-1 X kg-1 and from 2.1 +/- 0.1 to 1.4 +/- 0.1 ml X mmHg-1 X kg-1, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Elevated serum calcium and osteocalcin levels from calcitriol in preterm infants. A prospective randomized study

The hypothesis of this study was that pharmacologic doses of calcitriol (1,25-dihydroxyvitamin D3) would result in elevated levels of serum osteocalcin, the major noncollagenous bone protein, and calcium in infants of very low birth weight (less than 1500 g). Twenty-four infants of very low birth weight but of the appropriate weight for gestational age were matched in 250-g weight ranges and randomized into calcitriol treatment and control groups on the first day after birth. Treated infants received 4 micrograms/kg of calcitriol intravenously on entry and on the second and third study days. Controls did not receive calcitriol. Four infants from each group were hypocalcemic (serum calcium level, less than 7.0 mg/dL [less than 1.75 mmol/L]) on entry (five to 20 hours after birth) to the study. Seven infants received calcium replacement; data analyses with and without these infants were similar. Of the remaining 17 infants, eight were in the treatment group and nine were in the control group. Calcitriol significantly increased serum calcium and osteocalcin concentrations on days 2, 3, and 4 after birth compared with the control group. None of eight treated infants manifested hypocalcemia after calcitriol vs eight of nine controls. There were no acute changes in heart rate, respiratory rate, systolic blood pressure, or urinary calcium loss nor were there changes at the infusion site, but the diastolic blood pressure increased with treatment. Although high doses of calcitriol may elevate serum calcium concentrations in infants of very low birth weight, we suggest that the long-term or subtle biologic effects of high doses of calcitriol remain to be studied and that its routine use not be recommended at present.

Seasonal differences in serum vitamin D binding protein in exclusively breast-fed infants: negative relationship to sunshine exposure and 25-hydroxyvitamin D

Vitamin D binding protein (DBP) is the major carrier for vitamin D and its metabolites in serum. DBP increases in pregnancy and decreases in cirrhosis; no seasonal variation has been reported in adults. We observed significant seasonal differences in 41 exclusively breast-fed infants who were less than 6 months of age. Winter DBP concentrations exceeded summer DBP concentrations: 398 +/- 22 versus 297 +/- 20 micrograms/ml (mean +/- SEM). The mean concentration for spring and fall was 329 +/- 25 micrograms/ml. Maternal DBP concentrations did not differ by season. A sunshine exposure score, previously verified, was used to document time and body surface exposed to the sun. DBP was inversely related to sun exposure (r = -0.46, p = 0.005). Infant DBP was significantly and negatively correlated with 25-hydroxyvitamin D concentrations (r = - 0.38, p = 0.02). We speculate that serum DBP fluctuations are a response to varying vitamin D needs: increased serum DBP occurs in low vitamin D status to maximize uptake of vitamin D from skin.

Specific immune response in the respiratory tract after administration of an oral polyvalent bacterial vaccine

An oral killed polyvalent bacterial vaccine was assessed in a double-blind trial involving healthy volunteers. Three courses of oral vaccine were given over a 2-month period; each course contained 10(10) Haemophilus influenzae and 7 X 10(9) Staphylococcus aureus organisms. Immunity was assessed by monitoring antibody in saliva and serum over a 3-month period. No evidence of a nonspecific effect on immune parameters (immunoglobulin levels and Escherichia coli antibody) was detected in saliva or serum. An increase in H. influenzae antibody in saliva was detected in 55% of subjects receiving the vaccine compared with 6.7% of the placebo group. Antibody was associated with immunoglobulin A (IgA), IgG, and IgM, but the greatest increases over preimmunization levels were detected in the IgA class. No increase in serum antibody levels was detected. Subjects with higher preimmunization levels of salivary antibody to H. influenzae were less likely to respond to the oral bacterial vaccine. No increase in S. aureus antibody was detected in saliva or serum.

Dermatitis herpetiformis: a comparative assessment of skin and bowel abnormality

We reviewed 18 patients with a clinical diagnosis of dermatitis herpetiformis who were being treated with dapsone and were on an unrestricted diet. Diagnosis was confirmed by finding IgA deposits in the dermal papillae of unaffected skin. Dapsone was discontinued and biopsy of affected skin was carried out when the typical rash reappeared. The biopsy findings were graded according to the severity of the histological changes. Small bowel tissue from each patient was examined and graded by stereo- and routine microscopy. Thirteen specimens (72%) were stereomicroscopically abnormal; all 18 showed villous atrophy, either partial or subtotal; and in 13 (72%) the interepithelial lymphocyte count was increased. No correlation was found between the histological severity of the skin and the small bowel lesions. Seemingly the severity of the skin rash in dermatitis herpetiformis is no guide to the degree of small bowel abnormality.

Madagascarin, a New Pigment From the Leaves of Harungana madagascariensis

Extraction of the leaves of Harungana madagascariensis Poir. (Guttiferae) gave β-sitosterol, quercetin, diisopropyl 4,4'-methylenedicarbanilate (probably an artefact), and a new pigment, madagascarin. Mainly by spectroscopic methods the structure of the latter was established as 2,7'-biemodyl (1,3,8,l?,6',8'-hexahydroxy- 6,3'-dimethyl-2,Z'-bianthraquinone).

Effect of monosodium n-alkylsalicylates on spores of Bacillus subtilis

The effects of several monosodium n-alkylsalicylates on washed spores of Bacillus subtilis have been examined. None of the compounds was sporicidal, but in general they prevented dormancy induced by incubating the spores in water. This effect was related to the position in the ring and size of the alkyl groups substituted on the salicylic acid nucleus.

Antimicrobial activity of sodium n-alkylsalicylates

The activities are reported of sodium salts of several n-alkylsalicylic acids against Staphylococcus aureus, Pseudomonas aeruginosa, Mycobacterium phlei, and Candida albicans. The acids had alkyl substituents of 1 to 18 carbon atoms in the 3, 4, or 5 positions relative to the carboxyl group of salicylic acid. Generally, the antimicrobial properties were typical of anionic surface-active agents although the salicylates are more potent than most of these, particularly against S. aureus.